Folding step



FIG. 1 is a perspective view of a folding step showing my design;

FIG. 2 is a side elevational view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a front elevational view thereof; and

FIG. 6 is a rear elevational view thereof.

The ornamental design for a folding step, as shown and described.